Re: determining if a int is a power

[Paul Hudak]

But note that x `seq` x is equivalent to x, even operationally.  To see 
why denotationally, note that if x evaluates to _|_, so does x `seq` x. 
 And if x evaluates to a value v, so does x `seq` x.  To see why 
operationally, consider the two lists:

  let x = 1+1 in [x `seq` x]
  let x = 1+1 in [x]
Using conventional lazy evaluation in both cases, the term "1+1" is not 
evaluated until the head of the list is taken.  In other words, x `seq` 
x in no way hurries the evaluation of x.

  -Paul

Wolfgang Jeltsch wrote:
Am Samstag, 8. November 2003, 00:22 schrieb Hamilton Richards:
Also note that
        if x then True else False
is just a verbose way of writing
        x
Actually, it's just a verbose way of writing x `seq` x, but this detail is, of 
course, not interesting for beginners.

Wolfgang
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